The high levels of noise caused during press work by a crank-driven press has a bad influence on the health of people who live nearby a workshop, and is also liable to make operators hard of hearing.
Hitherto, to solve these problems in conventional manner, it has been suggested that the workshop is removed to an isolated zone, or soundproof walls are provided around the workshop. However, these are attempted cures, rather than preventive methods to keep the health of the operators and other people who live nearby the workshop.
It has been made clear through my research that in shock noise caused by and/or during press work, there are two kinds of noise, one being operational noise which is caused when working materials, and the other being vibration noise which is caused by the backlash produced when the momentum (kinetic enery) of the mechanical components and the metal mold is instantaneously reduced to zero. The latter vibration noise usually represents more than half of the total noise level issuing from a crank press machine. The method and device disclosed by this invention may accordingly effectively silence and eliminate the operational noise of a crank-driven press machine by actuating a brake means to prevent the momentum of components and metal mold from being instantaneously reduced to zero.